Molding machine



Jim. 3, 1939. E. J. BYERLEIN ET AL MOLDING MACHINE Filed Nov. 22, 1937 6 Sheets-Sheet l O O a 0 INVENTORS all 6 4 BY 3* 6. 51am ATTORNEY Jan. 3, 1939.

E. J. BYERLEIN ET AL MOLDING MACHINE Filed Nov. 22, 1957 6 Sheets-Sheet 2 ATTORNEY.

Jan. 3, 1939. E. J. BYERLEIN ET AL MOLDING MACHINE Tiled Nov. 22, 1937 6 Sheets-Sheet 3 INVEETORS ATTORNEY Jan. 3, 1939. EQJ. BYERLEIN ET AL MOLDING MACHINE 6 Sheets-Sheet 4 Filed Nov. 22, 1957 1 Mann, 1

E [8 INVfiI JNTORS BY 6 6. 43 m, M Ma. 1 WM ATToRNEYa Jan. 3, 1939. E. J. IBYERLEIN' ET AL MOLDING MACHINE ,Filed Nov. 22, 1957 6 Sheets-Sheet 5 INVENTOR6 w 'W irmmwwmw ATTORNEY.

Jan. 3, 1939.

E. J. BYERLEIN ET AL Filed Nov. 22, 1937 MOLDING MACHINE 6 Sheets-Sheet 6 INVENTORS ATTORNEY.

Patented Jan. 3, 1939 MOLDING MACHINE Erie J. Byerlein, Progreso. Tern, and Harrison E.

. Fellows, Wauwatosa, Wis, assignors to Mil wankee Foundry Equipment Gompany, Milwaukee, Wia, a corporation of Wisconsin Application November 22, 193'8, Serial No. 175,834

19 Claims.

This invention relates to improvements in in its rearward or withdrawn position, the inmolding machines. and more particularlyto a foundry molding machine adapted for jolting. squeezing, and stripping operations.

Molding machines of the type with which the present invention is concerned, are usually arranged to impart a rapid reciprocating movement to the molding flask to initially pack the molding sand around the pattern within the flask, after which the sand is subjected to a squeezing operation, followed by a, dogging operation, during which operation the pattern is removed irom the sand and flask. A fluid under pressure means is usually employed for reciprocating the various members of the molding machine for the above mentioned operations, and the squeezing or sand packing operation is effected against an elevated platen.

In certain types of molding machines, the platen is depended from an elevated car movable forwardly and rearwardly on tracks, the platen carrying car being arranged to be moved to a. 1, position over the molding flask for certain oper- C ations, and to be withdrawn therefrom for other operations. In the standard forms of molding machines havingthe car type platens, the weight of the platen car is borne by certain wheels which are engaged by suitably supported tracks. The jolting operations are performed when the car is withdrawn from or moved away from the mold, and it has been found that the jolting operation is apt to cause flat spots on the car wheels and depressions in the tracks with the result that when this condition obtains, difliculty will be encountered in eflecting proper movement and travel of the car.

An object of the present invention is to overcome the above-mentioned difllculty by providing, in a molding machine with a. car type platen, means for taking the weight of the car 01! of the 4 normal wheels and tracks. when the car is in its withdrawn position for jolting operations, so

, clination of-the tracks, with the provision of other means, serves to slow up the travel oi. the car when it is withdrawn, and to cushion it so as to minimize jars and bumps.

A further object of the invention is to provide,

in a molding machine having a car type platen, auxiliary inclined tracks which receive the car clination of said auxiliary tracks serving to give the car an initial desired forward momentum when the car is to be moved forwardly over the molding flask.

5 Another object of the invention is to provide, in a molding machine having a car type platen,

flask engaging hook members depended from the car and operable after the pattern drawing operation, to engage the molding flask and elevate 10 it and remove it from the molding portion of the machine, and as the platen car is moved rearwardly or withdrawn, the molding flask is carried therewith to a rear position, permitting it to be thereafter lowered on to a conveyor, and 16 thereby saving one entire operation necessary. during the use ofordinary molding machines.

A further object of the invention is to provide, in a molding machine, automatic means for preventing performance of the squeezing op- 20 eration before the platen carrying car is in its proper forward. position.

In the ordinary molding machines now in use, after the squeezing operation and just prior to the stripping or pattern drawing operation, both 25 tern plate is permitted to continue to lower. 30

Occasionally, there is an undesirable shock when the stripper plate is engaged by the dogging instrumentalities, and this is objectionable because 1 it may injure the sand mold. Also, ordinarily another shock occurs when the table. piston 36 reaches the bottom of its cylinder.

The present invention has as a further object, the overcoming of the above difliculties and provides a means of speeding up the travel of the members in their descent from the squeezing 40 position to the stripping position, and only momentarily retards the movement at the point where the dogging instrumentalities come into play, and the action of these members is accomplished so that the normal contact of the same with the stripping plate is cushioned to prevent damage to the mold, and thereafter the speed of descent of the table and pattern plate supporting table is accelerated and finally quickly checked without jars .or shocks just prior to the lowermost position of said members, with the result that production may be greatly accelerated with the advantage of accomplishing slow and careful pattern drawing.

g A further object of the invention is to provide amolding machine wherein the speed of action of the cylinders and dogging instrumentalities can be automatically controlled and can be regulated to suit the nature of the pattern and of the molding sand. 4

A further object of the invention is to provide a foundry molding machine which is of very simple construction, is easily and rapidly operated.

requires a minimum of control valves and mechanlsms, is strong and durable, and is well adapted for the purposes described.

With the above and other objects in view, the invention consists of the improved molding machine, and its parts and combinations as set forth in the claims. and all equivalents thereof.

In the accompanying drawings in which the same reference characters indicate the same or equivalent parts in all of the views:

Fig. 1 is a front view of the improved molding machine;

Fig. 2 is a side view thereof;

Fig. 3 is a fragmentary, perspective view of the platen car support and associated mechanism showing cushioning and locking means on the car; 1 e

Fig. 4 is an enlarged, fragmentary, detail view, partly in section, of the mechanism in the,car support, for cushioning the car as it is moved to its rearward or withdrawn posit on;

Fig. 5 is an enlarged front view, partly in section, of the platen car and showing the mechanism for operating the flask-engaging hooks;

Fig. 6 is a detail, sectional view taken on line H of Fig. 5;

Fig. 7 is a fragmentary, detail side view with the platen car in a forward position but with the valve operating lever engaged to prevent manipulation thereof;

Fig. 8 is a fragmentary, detail front view of the showing in Fig. 7;

Fig. 9 is a longitudinal sectional view through the platen car and supporting structure therefor, with the car in its forward position;

Fig. 10 is a view similar to Fig. 9 only with th car in its rear or withdrawn position;

Fig. 11 is a plan view of the platen car in its forward position, the associated supporting structure being shown in brokenlines;

Figs. 12 to 15, both inclusive, are vertical sectional views, somewhat schematic, of the jolting, squeezing and stripping cylinders, pistons, tables and frames, and of the operating and fluid controlling valves, the various views showing different positions of the various member during the performance of diiferent operations;

Figs. 16 and 1'! are similar views of several slight modifications in the mechanism, particularly with reference to the control of thestripping operation and descent of the pistons;

Flg. 18 is an enlarged, fragmentary view, with parts broken away and in section, of the rear portion of the platen car and its supporting structure, said view illustrating the wheels engaged with the rails and the pressure pads out of contact;

v 19 is a view similar to Fig. 18 only showing the wheels disengaged from the track and the pressure pads in mutual contact;

Fig. 20 is an enlarged, fragmentary, detail view of certain mechanism associated with the machine table 'and stripping frame whereby a valve operating mechanism may be actuated to automaticall! admit air into the lifting hooks cylinder;

Fig. 21 is a top view of the showing in Fig. 20

with certain parts in section;

Fig. 22 is an enlarged, fragmentary detail side 7 view of another formof valve control mechanism for admitting air to the lifting hooks cylinder, said view also showing the connections which extend to the Jolt table; 1 Fig. 23 is an end view of the showing in Fig. 22; and 1 Fig. 24 is a plan view of the showing inFig. 23.

Referring to the drawings, and particularly to Figs. 12 to 17 inclusive, it will appear that a cylinder 20 is mounted within the base 2i (see Figs. 1 and 2) of the molding machine. The cylinder 20 is provided with a piston 22 which extends through the upper open end of the cylinder 20 and carries a jolt table or head 23 at its upper end. The head is of rectangular form and is provided with obliquely extending lugs 24 for slidingly receiving the upper portions of downwardly depending guide pins 25. Said guide pins 25 operate in guide cylinders 28 which are con are parallel to said cylinder. The guide cylinders also serve as dash pots and contain oil to cushion the downward movement of the guide pistons 25 and a stripping frame 2! which is secured to the upper ends of'said pistons. A stripper plate 28 is secured to the stripper-frame 21 while the head 23 is adapted to carry a pattern plate.

The major portion of the wall of the piston 22 is in spaced relation to the inner surface of the wall of the cylinder 20. The inner wall of the piston 22 serves as a cylinder for a piston 3i! forming part of the head 23. The smaller piston functions to jolt the flask 3! to pack the sand therein on its exhaust stroke, and the larger piston serves to squeeze the sand around the pattern 32 and to strip the pattern from the sand. Air is supplied to the large cylinder 20 by a pipe 23 which is controlled by a valve 34, and air is also supplied into the piston 20 by a pipe 4 l connected with a source of compressed air supply (not shown) and controlled by a suitable jolt valve (not shown). A portion of the pipe 4| may be flexible to permit movement of the piston. when air is admitted to the piston lll, it reacts so as to move the piston and table 23 carried thereby upwardly. The upward movement continues until a cylinder port 39 is uncovered, whereupon compressed air will escape or exhaust via a duct 51. Then, said piston will fall downwardly rapidly and the table 23 will strike the top of a cyl- ,inder head 20 whereby a severe Jolt or jar is imparted to the table and members carried thereby. The jolting reciprocations can be continued as longns air is supplied through the pipe I and "I2 (Fig. 2) is pressed downwardly, a valve port 21 will be opened, permitting flow of air through the pipe 33, and by the same action of the valve handle, another valve port 38 will be closed. The

air enters under piston 22 and both pistons, and all of the members carried thereby, are moved upwardly until the flask reaches a suitable platen 42 which has been moved over the base and cylinder. The air is kept on until the desired pressure has been built up under the piston 22 to properly squeeze the molding sand, this action being best shown in Fig. 13.

Heretofore, after the squeezing operation and 'nected to the cylinder 20 and the frame 2| and rin desc n -.o ihepi on and ia r r en s;. de nw d a pw y bee ase.qt leak of thastripping. framev by the dogging; members and final descent oi the pistons, dificulties have been encountered. Ifthe doggingmembers errgage the; stripping frame too -f orcefully,the mold may be. jarred: anddamaged and if; the recession is too ,rapid after engagement ofsaid dog-W K members. suction will cause, damage, to-thev moldhlttis,therefore, also desirableto imme-u diatel-y, thereafter retard thedescent ofqthe pistons,,,momentarily to effecta SIOWAI'ldCBLX'BfUl. pattern draw. Also it is undesirable to have the pistons ,strike the bottom of the cylinder. 20 too forcefully. With the foregoing in mind, the

present'invention provides means for correctly, meeting these contingencies and conditions. Consequently, in the present invention means are provided for reducing the "time interval for the drop of the stripping frame 21 onto the rollers. 43 of pivotal dogging arms 44 and to have the frame contact said rollers without a shock or bump; to commence drawing the pattern 32 from the molded sand in the flask 3| immediately thereafter and slowly at a desired speed to suit the nature of the pattern and sand; and to thereafter speed up the rate of descent of the members after pattern withdrawal is correctly under way; and finally to check and cushion the fall immediately before the piston 22 and the table 23 have reached their respective seats.

Referring again to Figs. 12 to 15 inclusive, it

low the piston 22. The exhaust air flows through pipe 33 into the intermediate compartment of valve 34, through open valve port 38 and then into the casing of the auxiliary valve 45, via a connecting conduit 46. Obviously, the piston 22 will proceed to drop from its squeezing position and just before the stripping frame 21 makes contact with the rollers 43,- a finger 41 adjustablydepended from the lower portion of the head 23 will contact a roller 48 on the end of a pivotal arm 49, and said arm will be forced to the right in the drawings to actuate a valve plunger 50. The action which takes place is shown in Fig. 14 and it will be noted that the plunger 50, which is yieldably mounted, carries within the valve casing a valve 52 which is moved to close a port 53 preventing flow of air into the other side of said valve casing. understood that after the squeezing operation the dogging arms 44 have been swung outwardly from the position of Fig. 12 to the position of Fig. 13 by the usual means which may include an operatingbar 54. Because of the position of thevalve 52 just efl'ected,:air will be trapped in the system below the piston 22 and the 'downward movement of saidmember will be checked and cushioned prior to thetime thatthe stripping frame actually comes to rest on the rollers terns and: with various kinds of" "molding. "sandin- Notwithstanding athe: closure or the :valve: port "by the. valve; 52; I the piston 22 will neverthe It should be age iarouridlthe [valve plunger d i qr e i igpqntiniws; frame actually gently settle Ion thedlolle the o in arm --..The vspe d,a ;w i h: t

i on. ;x ree i aid t and e S eed i" pattern draw depends n the extentto. whic the adjusted lengthgof plunger,

valve 52 closes ort 53,,and this is 'controlled byi" the sand in the flask, which'is, highlydesirable.

During continued descent of the piston?! and table 23, the roller 48 of the varm 49 rides upwardly on the inclined edge of a lug 55 on the finger 41 and eventually clears the lug and finger, as in Fig. 15. The lug 55 can beshaped and inclined as desired .tosuit any required condition as to speed of pattern withdrawal, acceleration, or the like. After there has, been-suffle cient slow downward creepingof the pistonand after the lug 55 has passed below the roller 48 the yieldable plunger 50 will automatically move to the left with respect to the drawings and the port 53 will be opened, speed of .fall of the pis ton and table will be accelerated until said piston. engages its seat inits lowermost position. Ifit is desired to cushion the final; seating ofv the piston, the finger 41 :(see-Figs. =16, and 1'7) may beformed with an additionallug or cam surface 55' which is engagedatthe proper time by the roller-48 to again moveutheplunger 503 and close the valve port 53; g

During normal jolting operations, it" is not desirable for the finger "to .engage'and move the valve plunger 50. Hence, during these opduring jolting.

in Fig, 17. In this form'of the invention, there is carried by the piston 22, througha vertical rod 56, a depending finger 41. Said rod has its lower end threaded into the basei'flan'g'e of said.

pistonand is vertically: adjustable. With this construction, inasmuch as the piston 22 does not move during jolting operations, the finger '41- will not be movediand it will not benecessary' to employ special means for holding the arm 49 away from said finger, asbrought .out in the preceding paragraph; In-this case-"during -jolt-.

ing, the upper cam or'lug 55- on said finger'will hold the valve plunger 50 inwardly to. maintain the valve 52 in closedpositioni Escaping air from the jolting piston 30' escapes through ports 39'and thence to theatmospherethrough duct 51.

In the present inventiomiexh aust air; which: is clean, is utilizedin'the vspace etbove the flange" portion of the piston 22- .and said 'spa'cei -is filledv while Jsaid piston is falling and creating-a sue-- tionfltherewithin. In"Flg..13.:the-pist0n 22 .is in: its uppermost position .and after the sand in the; flask. 3i has been squeezedxagainstgthe platen' 42,aii' below-thepiston: 22 is'permitted to ex.-. haust -throug'hxthepipe 33, the' intermedi'atechamber of: the valve'i34, through-t Fthe conne'ca.

tion 45,. through thecasingiof :the auxiliary-valve 4,5, and then through the conduit-e40v and-finally into the chamber 58; Lthe'f latter chamber 'belng A slight additional modification is illustrated between spaced portions of the walls of the pistons 22 and walls of the cylinder 28. The air entering into this chamber can exert a force against the lower flange of the piston 22 to help to accelerate the fall of said piston. More important, however, this arrangement supplies clean air to the chamber 58 and this continues as the piston continues to fall, which would not be the case if exhaust air from below the piston 22 were conducted directly to the atmosphere, which is common practice. Any excess air in said chamber 58 is naturally. expelled to the atmosphere through the duct 51. Or said air may be conducted to an air cleaner or breather, as desired.

It should also be observed that the air which is exhausted through the chambers, as described, is oil laden, and this helps to lubricate the sliding surfaces.

As will be clear from Figs. 1 and 2, the molding machine in general is of the type wherein the faten 42 is depended from the forward end portion of a slidable platen car 80. The base 2| of the machine has on opposite sides thereof upwardly extending arms or supports 8i which carry a platen car housing 62 or the bar structure. In general, said housing includes a top 68 and vertical spaced sides 64, the inner faces of said sides carrying tracks or rails 65 and 98 along which the platen car 80 is normally movable. As will appear from Fig. 11, a transverse shaft 66 journaled through the sides of the platen car carries a pair of spaced forward wheels 61, while stub shafts 68 carry rear wheels 89. During the major portion of forward and rearward propulsion of the platen car, said wheels 61 ride on the housing rails 65 and the wheels 68 ride against upper rails 98, as the center of gravity of the car is forwardly of the front wheel axes.

when squeezing operations are to be performed, as described heretofore, the platen 42 must be in position over the cylinders and table. Hence, at this time, the platen carrying car 68 should be in its forward position relative to its housing. One of the objects of the present invention is the inclusion of means in the improved molding machine to prevent performance of the squeezing operations until and unless the platen carrying car is in its forward position with the platen correctly disposed for these operations. To this end, the operating lever 36 of the squeezing valve 84 (shown schematically in Figs. 12 to 16 inclusive), is equipped with an extension rod 10. The upper end portion of said rod extends slidably through a box-like casing II and is normaly urged downwardly by a confined. coiled spring 12. The upper extremity of said rod has pivoted thereto the inner end portion of a control lever 13. Said lever 13 is intermediately pivotally mounted on a boss on the housing side 64, as at 14.

By reference particularly to Figs. 7 and 8, it will appear thatia side of the upper portion of the rod 10 carries a block 15 adapted, under certain conditions, to have its top edge engaged unmovable plunger 88.

tion for squeezing, the arrangement is as illustrated in Fig. 7 and the dog 11 locks the rod II and prevents movement of the lever 18 and consequent operation of the squeezing valve.

When the platen car is, however, moved to its extreme forward position for squeezing, a rear lateral flange or plate I8 on the car engages a slidable plunger 88 and causes its end portion to move and engage the dog 11 to swing the dog to a rod releasing position. Thereupon the handle 13 is free to be moved to operate the squeezing valve.

In a molding machine having a platen car, when Jolting operations are performed, the platen car is in its rearward or withdrawn position. Without the feature to be described, and according to standard practice, when this is the condition, the weight of the car and platen is borne directly by the car wheels and the rails on which said wheels rile. This is objectionable because the rails and wheels must be maintained in proper condition to insure free travel of the car, but due to the shocks of jolting operations, in time fiats" will be formed on the wheels, and depressions or irregularities will be formed in the rails.

The above objections are overcome in the present invention wherein the front axle 88 of the platen car has fast thereon a pair, of auxiliary wheels 8| of less diameter than the wheels 81. Mounted on the lower portion of the rear of the housing 62 and alined with the wheels II are a pair of inclined stub rails 82 which are upwardly, rearwardly inclined. The result is that when the platen car is pushed sufficiently rearwardli' the auxiliary wheels 8| will engage and ride upwardly on the stub rails 82. This will remove the front wheels 61 from the main rails 88 and the rear wheels 69 from rails 98, bringing the wheels '69 into contact with the rear end of rails 85, and the car will be supported by the wheels." on the stub rails 82. This is the proper position for the platen car during jolting operations and hence the usual wheels and rails will not be engaged and subjected to bumping and jolting actions such as would form defects therein.

As the platen car is usually pushed rearwardly with some force, means are provided for cushioning it as it reaches its rearward position for also releasably holding it in said rearward position on the inclined stub rails 82. The under surface of the top 63 of the car housing, intermediate the sides and just forwardly of the stub rails 82, carries a pair of adjacent cylinders 88 and 84. The uppermost cylinder 88 has a spring surrounded plunger 85 therein, which projects out of the forward end of said cylinder. An upper media] portion of the platen car 68 carries an upstanding bracket 86 in the end of which is ad- ,iustably threaded a rearwardly projecting pin 81. With this arrangement, when the platen car reaches its rearward position, the end of the pin 81 engages the resilient plunger 85 and due to the yielding movement of the plunger, there is a cushioning or shock absorbing effect.

The lower cylinder 84 also has extending longitudinally therein a spring surrounded yieldingly The forward end of said plunger, outwardly of said cylinder, carries a cap 89 having a projecting lower lug 88'. A pawl II is pivotally mounted on the car bracket 88 and a cupped arm 86 of said pawl has a slidable rod 82 extended therethrough, one end portion of said rod being securedto a pivotal operating orlatch handle 88. When said pawl pivots in one direction, it compresses a confined coiled spring 94 on the rod 02. ;The outer free end of the pawl is.

provided with a shoulder ll.

. gases the cap lug 09', as in Fig. 4. Due to the yieldability of the plunger 80 which carries the cap 09, slight recoil is permitted, but the engagement shown in Fig. 4 is eflective to maintain the" platen car in its rear position wherein the auxiliary wheels II are engaged on the stub rails 02. When the platen car is to be moved forward, the operator first lifts upwardly on the latch handle 93. This action, through the rod 92, will rock the pivotal pawl in a direction to disengage it from the-plunger cap 09, whereupon the car is free to be moved forwardly, and the inclination of the stub rails 82 plus the built-up spring tension on member 00 will give the car an initial desired forward impetus.

With reference to Figs. 18 and 19, the platen bearing pads I20 and rear striking pads I2I. Asv

pressure is applied to the center line of the platen, forwardly of the front axle, the front wheels 6] are lifted from track 65 until the bearing pads I20 engage. At this time, the platen car' will rock and the rear striking pads I2I engage the heels of the frame 04. Fig. 19 illustrates attainment of the last-mentioned condition. If, through inadvertence; the squeezing pressure should react on the platen car rearwardly ofthe front wheel axis, the rear striking pads I2I will not contact the frame heels, and in this event, upward forces will be against wheels 69 at the time when the same are in engagement with'the yieldable track section 99. The yieldability of said track section then relieves the wheel bearings of excessive pressure. This upward movement is, of course, limited, inasmuch as the front bearing pads I20 will -the wheels 01 or 69.

limit the movement and will take most of the squeezing pressures. With the arrangements just described, there is a minimum of clearance at the bearing pads for the free movement of the platen car, but at the same time it prevents squeezing pressures being exerted against the bearings of Figs. 3, 10, 18 and 19 disclose the rails within the rear upper side portions of the platen car housing 09, previously referred to. The upper rails 90 and the sections 99 thereof are yieldingly mounted in slotted bosses I00. The yielding rail sections are depended from vertically movable rods III, and said rods are movable against the tension of confined coiled springs I02. .These yielding upper rail sections 99 are only engaged by the upper portions of the rear wheels 09 of the platen car when the car is in its forward position for squeezing operations.

After the pattern drawing operation, the flask with the mold therein is to be removed from the supporting member on the machine base, so that another flask may be quickly substituted for continued operations. At this stage, which follows the squeezing operation, the platen car is in its forward position. The top forward portion of the platen car has transverse apertured supporting channels I 09 connected to and extending on opposite sides of a bell casing- I09 and above transverse slotted openings I05. In a selected register-- ing opening I00, of each ofthe channels, there is a pin I01 from which pivotally depends, 'a'fiask hook I00, said hooks extending through and being movable in theslotted openings I00. I

From Fig. 5,'it will appear that the top of the platen car has formed thereon a cylinder I09 in which 'is slidably fitted a piston -I I0. The upper end of the piston supports the bell casing I which also encloses the cylinder and piston. The piston is vertically slidable within the cylinder. and upon a central stud III. The lower portion of the cylinder has an airport II 2 from which extends a hose II3. Said hose may be connected the cylinder I09 below the piston IIO, said piston is raised, elevating with it the bell casing I04 and the hook carrying channels I03. The limit of upward movement of the piston is controll by ahead lllo'nsaid guide stud III.

When the piston in said cylinder is elevated through compressed air means, the hooks I00 will swing toward each other, riding on rollers I IS. The platen car is so located-relative to the flask 3| that this movement ofthe hooks I00 will cause the lower ends of the same to engage under the upper peripheral flange of the flask. Further upward movementof the portion IIO lifts the mold on of the flask supporting table so that the dogging arms 44 can beirmnediately tripped'to return the stripping frame 21 to normal position. Simultaneously, the platen car is moved rearwardly in readiness for the jolting operation relative to a new flask and by virtue of the rearward movement of the platen car, the first fiask with the finished mold therein is carried by the hooks to a position over a conveyor H0 at the rear of the machine. At this time, by exhausting the air from below the piston H0, said piston and belly bracket I24 and roller, adapted to pivot in the opposite direction. The bracket I29 is connected iigsthe dogging arms link 54 by means of a link During jolting operations, the dogging arms 44 (Figs. 12-16) are in their inner positionsand hold a roller I26 out of engagement with a finger I21, said finger being depended from the jolt table 23. Hence the valve does not operate during the jolting operations. During squeezing operations, the dogging arms 44 move-outwardly,

transmitting motion through link 54 (Figs. 15) and link I25, to bring the roller I29 into alinement with said finger I21. Prior to the jolt table reaching its seat and just before the stripping frame engages the dogging arms and during a pattern drawing operation, said finger I21 contacts said roller I26 and forces a set screw III to engage and push a yieldable stem I29, said stem controlling a valve in a casing I30 whereby compressed air, admitted into the valve casing I" through a connection l3i, may pass from the valve casing through the connection III to the lifting hooks cylinder I09. By vertical adjustments of the finger i2! and adjustments of the set screw ill, the discharge of air via connection 8 to the lifting hooks cylinder can be regulated to suit the particular pattern and flask.

In Figs. 20 and 21 there is illustrated another arrangement for controlling air fiow to the lifting hooks cylinder I". This arrangement utilizes a pair of cam fingers I32 and I, the first of which is attached to the machine stripper frame 21 and the other of which is attached to the jolt table 23 of the machine. During the jolting operation, the stripper frame cam finger I32 contacts a roller Ill on the main support I35, which-support is pivotally mounted on abracket Ill attached to the base of the molding machine. The engagement of said cam finger with said roller serves to hold the entire mechanism out of engagement with the jolt table cam finger I33. The cam roller I is urged toward said finger ill by a spring I". when the tables of the molding machine move upwardly for a squeezing operation. the spring tension causes the bracket Ill to be held in a position of allnement with the cam finger I32 and during this operation said cam finger is in a raised position by virtue of the dogging arms 44 which are in a position to support the stripping frame. The jolt table cam finger I, in this situation, engages another roller it! which is supported by the valve bracket Iii. Bald engagement causes a valve stem I" to be engaged and yleldably movedby a set screw I. said valve stem operating mechanism within a valve casing Ill to permit air fiow through the casing. The spring Ill maintains the bracket I in a suitable position so that the set screw I will effect the engagement just described. Air is admitted under pressure into the casing Ill by a suitable connection (not shown) and air leaves the other side of the easing through another connection and is conducted to the lifting hooks cylinder by the connection Iii (Fig. In this arrangement, the finger I" is likewise susceptible of vertical adjustments and the set screw I is also adjustable to admit air to the lifting hooks cylinder in a manner to suit the particular pattern and flask.

Air is exhaustedfrom the lifting hooks cylinder lill through a tubular connection I" (Fig. 4) which enters the rear of the bore of the plunger 86. When the platen car is pushed to its rearward position, the adjustment screw 81 contacts the plunger 85 and this causes an opening of an exhaust valve I43. Movement of the plunger 85 is ultimately yieldingly repelled by a coiled spring I surrounding said plunger. The rate at which air is exhausted from below the piston liil (Fig. 5) in order that the mold may begently deposited upon a storage conveyor, is

controlled either by an adjustable member in a plug as at ill in Fig. 4 or by having a vent in said plug of a suitable diameter.

When the mold is d'epended by the hooks I08, the operator pushes the car 'rearwardly and trips the dogging arms. Thereupon the intake valve and the exhaust valves of the mechanism operate simultaneously. If the dogging arms 44 should be tripped before the car reaches its rear position, the molds will nevertheless hang from the hooks Ill as there is sumcient air trapped below the piston lit to support the load.

Obviously, by shifting the hook depending pins II! to any selectedapertures in the channels I", the hooks may be adjusted for flasks of varying sizes.

From the foregoing description it will be seen that the improved foundry molding machine is efiicient in its operation, is novel, and is well adapted for the purposes described.

What is claimed as the invention is:-

1. In a molding machine having jointly and severally reciprocable pistons and supporting members carried thereby for the performance of squeezing and pattern drawing operations, means for lowering said pistons and members from squeezing position, means for intercepting one of said supporting members during the lowering of the pistons for pattern drawing, and means adjustably and interchangeably associated with one of the supporting members for retarding the speed of descent of said pistons at a selected point prior to the operation of said intercepting means and for accelerating the speed of descent of said pistons at a selected point after the pattern drawing is under way and for finally retarding the descent of said'pistons and cushioning the seating of the same as they approach their lowermost positions.

2. In a molding machine having jointly and severally reciprocable pistons and supporting members carried thereby for the performance of squeezing and pattern drawing operations. means for lowering said pistons and members from squeezing position. means for intercepting one of said supporting members during the lowering of the pistons for pattern drawing, and automatically operating, regulatable valve controlled, fluid pressure means adiustably and interchangeably associated with one of the supporting members for retarding the speed of descent of said pistons at a selected point prior to the operation of said intercepting means and for accelerating the speed of descent of said pistons at a selected point after the pattern drawing is under way and for finally retarding the descent of said pistons and cushioning the seating of the same as they approach their lowermost positions.

3. In a molding machine, reciprocable members for supporting and moving a molding fiask, a platen adjacent which the flask is adapted to be moved, a movable car on which said platen is mounted whereby the platen may be positioned over the flask for squeezing or withdrawn therefrom, valve controlled'fiuid pressure means for moving said reciprocable members, and means for preventing operation of said valve except when the platen-carrying car is imposition with the platendirectly alined with the flask.

4. In a molding machine, reciprocable members for supporting and moving a molding fiask, 'a

platen adjacent which the flask is adapted to be moved, a movable car on which said platen is mounted whereby the platenmay be positioned over the fiask for squeezing or withdrawn therefrom, valve controlled fiuid pressure means for moving said reciprocable members, and automatically operated means for preventing operation of said valve except when the platen carrying car is in position with the platen directl alined with the fiask.

. 5. In a molding machine, reciprocable members for supporting and moving a molding flask,a platen adjacent which the flask is adapted to .be moved, a movable car on which said platen is mounted and movable from a flask engaging position to a withdrawn position, valve controlled fluid pressure means for simultaneously moving said reciprocable members, latch means for preventing operation of said valve except when the car is in the flask engaging position, and means for automatically releasing said latch means when the caris moved into its'flaskengaging position.

6. In a molding machine, reciprocable members for supporting and moving a molding flask, a platen adjacent which the flask is adapted to be moved, a movable car on which said platen is mounted and movable from a flask engaging position to a withdrawn position, valve controlled fluid pressure means for simultaneously moving said reciprocable members, latch means for preventing operation of said valve except when the car is in the flask engaging position, and means carried by the car for automatically releasing said latch means whenthe car'is moved into its flask engaging position.

'7. In a molding machine having a frame and an upper supporting structure, primary rails within said supporting structure, a platen car,

primary wheels on which said car is mounted eng'ageable with said primary rails for propulsion of the car relative to said supporting structure from a withdrawn position to a projected operative position, and means for disengaging said pri mary wheels from said primaryrails and for otherwise supporting the car within the supporting structure when the car is in its withdrawn position.

8. In a molding machine having a frame and an upper supporting structure, primary rails within said supporting structure, a platen car, primary wheels on which said car is mounted engageable with said primary rails'for propulsion of the car relative to said supporting structure from a withdrawn position to a projected operative position, inclined stub rails within the supporting structure, and auxiliary wheels on said car engageable with said stub rails when the car is in its withdrawn position whereby the primarywheels are disengaged from the primary rails.

9. In a molding machine having a frame and an upper supporting structure, primary rails within said supporting structure, a platen car, primary wheels on which said car is mounted from each other for mold engaging and mold' engageable with said primary wheels for propulsion of the car relative to said supporting structure from a withdrawn position to a projected operative position, inclined stub rails within the supporting structure, auxiliary wheels on said car engageable with said stub rails when the car is in its withdrawn position whereby the primary wheels are disengaged from the primary rails, and shock absorbers for cushioning the impact of the car when it reaches its withdrawn position.

10. In a molding machine having a frame and an upper supporting structure, primary rails within said supporting structure, a platen car, primary wheels on which said car is mounted engageable with said primary rails for propulsion of the car relative to said supporting structure from'a withdrawn position to a projected operative position, upwardly, rearwardly inclined stub rails within the supporting structure, auxiliary wheels on said car engageable with said stub rails when the car is in its withdrawn position whereby the primary wheels are disengaged from the primary rails, shock absorbers for cushioning the impact of the car when it reaches its withdrawn position, and yielding means for releasably retaining said car on the inclinedstub rails.

releasably engaging a mold for removal of the mold from its support and for movementof the mold with the platen supporting member, and fluid actuated piston means for moving the engaging portions of saidhooks toward and away releasing purposes.

12. In a molding machine, reciprocable members for supporting and moving a molding flask, a platen supporting member relative to which the flask is adapted to be moved by said reciprocable members, means permitting movement of the platen supporting member from over the reciprocable members to a withdrawn position laterally thereof, means depended from the platen supporting member for automatically, releasably engaging a mold when the platen supporting member is in its normal position, means controlled by downward movements of said reciprocable members for operating said mold engaging members, said means carrying the mold with it during lateral movement of the platen supporting member, and means controlled by movement of the platen supporting member to its withdrawn position for automatically eflecting releasing operation of said mold engaging members.

13. In a molding machine, reciprocable'members for supporting and moving a molding flask, a platen against which the flask is adapted to be moved for squeezing operations, a platen car supporting structure, a car on which said platen is mounted slidable in said structure and movable from a squeezingposition over the flask to be withdrawn position, and, yielding members against which supported portions of the car may bear during abnormal squeezing operations.

I 14. In a molding machine, reciprocable members for, supporting and moving a molding flask, a platen against which the flask is adapted to be moved for squeezing operations, a platen car supporting structure, rails therewithin, a platen car slidable ,within said structure andhaving front wheels and rear wheels selectively engageable with said rails, bearing pads between portions of the supporting structure, the center of gravity of the car being forwardly of the axis of said front wheels, certain sections of said rails .being yieldable, and means for causing a slight one of said supporting membersduring the lowering or the pistons for pattern drawing, and automatically operating regulatable valve controlled,'fluid pressure means for retarding the speed of descent of said pistons at a selected point prior to the operation of said intercepting means and for accelerating the speedoi' descent oi said pistons at a selected point after the pattern drawing is under way, said last-mentioned means including an eccentric surfaced flnger ad- Justably depended from one or said supporting members and a valve plunger tor the valve of the fluid pressure means formed with a head for engagement with eccentric suriaceportions of the flnger during predetermined positions or said supporting member.

16. In a molding machine. reciprocable members for supporting and moving a molding flask,

a movable platen adjacentswhich the flask is adapted to be moved when the platen is in a position over the flask; the platen being movable from-said position to another position remote from the flask, valve controlled fluid pressure means for moving said reciprocable members, and meanscontrolled by movement of the platen for preventing operation of said valve except when the platen is directly over the flesk.

17. In a molding machine, reciprocable members for supporting and moving a molding flask, a platen against which the flask is adapted to be moved for squeezing operations, a platen car supporting structure having guides therein, portions of said guides being yielding, a car on which said platen is mounted and having wheels engagsition engagin the yielding portions of said guides, and automatic means for preventing movement of said reciprocable members for squeezing operations except when said car is in the last-mentioned position.

18. In a molding machine having a frame and an upper supporting structure, primary rails within said supporting structure, a platen car,

primary wheels on which said car is mounted engageable with said primary rails for propulsion oi. the car relative to said supporting structure from a withdrawn position to a projected operative position, means for disengaging said primary wheels from said primary rails and (or otherwise supporting the car within the support-' ing structure when the car is in its withdrawn position, and retracted and latched cushioning members against which, the car is engaged when in said withdrawn position, said car supporting means and said retracted cushioning members being effective to give the car an initial forward impetus upon release of the latch.

19. In a molding machine, reciprocable members for supporting and moving a molding flask, a platen supporting member relative to which the flask is adapted to be moved by said reciprocable members, means permitting movement of the platen supporting member from over the reciprocable members to a position laterally thereof, and means depended from said platen mold for removal oi the mold from its support and for movement of the mold with the platen supporting member, said last-mentioned means being eilective to raise and lower the mold.

' ERLE J. BYERLEIN. 

